You are saying the US they allow "full-size" (8-12 oz) contact lens solution bottles? wow, that is news to me. After the liquid restrictions came into effect I always pack my large size - and just carry 2oz bottles on. And never had a problem with that size anywhere. I use Renu and they have those smaller sizes. I don't know about the "plain jane" saline sizes.
Really surprised to hear that the US would allow the full-size, esp. if already opened and not sealed. But as I said, I don't know because I never tried it...